Sectional boom for cranes



March 5, 1963 A. O. F ELKNER SECTIONAL BOOM FOR CRANES Filed Dec. 15, 1960 E16- 5 INVENTOR.

,4; PH/E' 0 f5; mwse BY W United rates 3,080,668 SECTIGNAL 300M FOR CRANES Alphie G. Felemer, Paimdale, Calif. Filed Dec. 15, 1960, Ser. No. 7 6,010 6 Claims. (Cl. 212-144) This invention relates to sectional booms for cranes, and included in the objects of this invention are:

First, to provide a sectional boom for cranes wherein two or more boom sections may be readily connected by manipulation of the crane with assistance, consisting essentially in merely latching the sections together after they have been connected.

Second, to provide a sectional boom which does not alter the function of or in any manner interfere with the operation of the boom, or reduce its strength.

Third, to provide a sectional boom which, though readily and quickly connected or disconnected when desired, is firmly secured against accidental separation when in operation.

With the above and other objects in view, as may appear hereinafter, reference is directed to the accompanying drawings in which:

FIGURE 1 is a fragmentary side view showing a pair of boom sections in pmtially connected relation;

FIGURE 2 is an end view of one of the boom sections taken substantially along the line 2--2 of FIGURE 1;

FIGURE 3 is an end view of the other boom section taken substantially along the line 33 of FIGURE 1;

FIGURE 4 is a fragmentary sectional view taken through 44 of FIGURE 3, showing the two boom sections in interconnected relation;

FIGURE 5 is a fragmentary sectional View through 55 of FIGURE 3;

FIGURE 6 is a fragmentary sectional View through 6-6 of FIGURE 3 showing the two boom sections in interconnected relation;

FIGURE 7 is a sectional view through 7-7 of FIG- URE 3 showing the boom sections in their interconnected relation.

The sectional boom includes two or more boom sections 1 and 2 of square or rectangular cross section and comprising longitudinal rails 3 and brace struts 4. The ends of the beam sections are provided with mating end plates 5 and 6.

The end plate 5 on the beam section 1 is provided at its upper margin with a hinge bar 7 which is firmly welded thereto. The hinge bar projects above the plate 5 and also projects forwardly thereof so that its axial side coincides with the forward face of the plate 5, as shown best in FIGURE 7.

The end plate 6 is provided at its upper margin with a semicylindrical hinge hook 8 positioned to fit over the hinge bar 7 when the two end plates are in contiguous relation, as shown in r IGURE 7. The hinge book 8 is reinforced by longitudinally extending ribs 9 which are joined to a reinforcing bar 1% extending across the boom section 2 adjacent the end plate 6.

The sides of the boom section 2 adjacent the upper margin are provided with guide strips 11, which project beyond the boom section 2 on opposite sides of the boom section 1, to aid in guiding the boom section 1 into posi tion for interengagement with the hinge bar 7 and the hinge book 8.

The upper side of the end plate 6, a short distance below the hinge book 8, is provided with two perforations 12. The end plate 5 is provided with a pair of mating pins 13 having tapered extremities so that, as the two end plates move into contiguous relation, the pins 13 enter the perforations 12 so as to dispose the boom sect-ions 1 and 2 in axial alignment.

The end plate 6 is provided adjacent its lower margin 3,089,068 Patented Mar 5, 1 963 ice with a horizontal row of slots 14, preferably arranged in two pairs. Secured to the end plate 5 is a corresponding set of latch hooks 15 having upwardly directed hook elements 16. The latch hooks 15 are adapted to enter the slots 14, and the hook elements 16 project into the boom section 2 a sufiicient distance to define with the back side of the end plate 6 upwardly directed channels 17 which receive a transversely disposed latch bar 18 disposed adjacent the back side of the end plate 6.

The lateral extremities of the latch bar 18 extend into cylindrical guide cages 19 disposed in the lateral corners of the boom section 2, the guide cages having accommodation slots for the ends of the latch bar 18. The extremities of the latch bar 18 are provided with vertically extending guide pins 20 which project through the upper ends of the guide cages 19. Springs 21 are disposed within the guide cages 19, around the guide pins 20, and urge the latch bar 18 downwardly into the channels 17.

Centered on the back side of the end plate 6 below the latch bar 18, is a cam 22 mounted on a stub shaft 23 journaled in the end plate 6. A handle 24 is attached to the cam 22. The cam has a minor diameter permitting the latch bar 18 to occupy a lower position, and a major diameter dimensioned to hold the latch bar 18 clear of the slots 14-, as shown in FIGURES 3 and 7. A cam face between the minor and major diameters of the cam enables the cam, on partial rotation, to raise the latch bar from its normal latching position to its raised position. This is accomplished by manual movement of the handle 24.

The central portions of the end plates 5 and 6 are provided with openings 25 through which extend the cableswhich are threaded through the assembled sectional boom. The sections of (the sectional boom are assembled as follows:

The boom section 1 is pivotally connected to the crane,

force of the springs 21 until the latch bar snaps into thechannels 17. Succeeding sections of the boom, each having a plate 5 at one end and a plate 6 at the other end, may be joined in a similar manner.

It will be observed that the operation joining these sections or" the boom may be accomplished almost entirely by the crane operator with a minimum of assistance,

which may consist solely in the attachment of a lifting hook 26 to the boom section 1.

in disassembling the boom sections 1 and 2, the extended end is brought into contact with the ground, the cable is temporarily attached to the boom section 1 and sufiicient upward force is applied to relieve the load on the latch hooks 15, whereupon the latch bar 18 is manually raised to the position shown in FIGURE 3; thereupon, the boom section 1 is lowered, causing pivotal movement of the hinge bar 7 in the hinge hook 8, until the latch hooks v15 are disengaged, as represented in FIGURE 1.

While a particular embodiment of this invention has been shown and described, it is not intended to limit the same to, the exact details of the construction set forth, and it embraces such changes, modifications, and equivalents :of the parts and their formation and arrangement as come within the purview of the appended claims.

What is claimed is:

1. A sectional boom, comprising: a pair of completely separable boom sections having confronting coregistrable end plates; an open hinge hook disposed across the upper margin of one of said end plates;.a hinge bar disposed across the upper margin of the other of said end plates, said hinge bar being movableradially into said hinge hook for cooperation therewith,ato move'said'end plates'int'o' contiguous" coregisteringi relation; and latch means 1 for securing said end plates in contiguous relation. I

2; A 'sectionalboom, 1com'prising: a pairof 'com'pletely separable boom sections having: confrontingv coregis=- trab'le end plates; an open hinge hook disposed across'thei upper margin of one of said 'end' plates; a-hinge bar dispbsed -acrosstheupper margin of the" other of said end' plates, said hingebar beingtmovable radially into said hinge hook for cooperation therew-i=th,.tomove said end plates into I contiguous coregi'ste'ring relation; latch ele'- ments protruding from one'of said end plates adjacent itslower end, the other of said endplates having mating slots to receive" said latch' elements when said plates are in coregistering relation; anda' latch 'barcarried by said other end" plate for engagingzand receiving said latch elements;

3; Asectionalboorfi', comprisihgrapairof completely separahle'boom sections having;confrontingicoregistrable end plates; an open hinge hook disposed a'cross the' upper m'arg'inof one of said end plates; ahinge bar disposedaci'osstheupper' margin of the other of said end plates, said 'h'in-geba'r being 'movable radially into said hinge hook for cooperation' therewith; tomove said e'n'd plates into contiguous" co'r'e'gistering relation; a plurality of latch :elements having. hook extremities protrudingfrom one of said end'plates, theoth'er of said end plates having'slots tit-accommodate said latch elements whensaid plates are in coregistering'relation; .alatch bar-disposed behind said other end plate and in transverse relation to said latch elements; spring means normally holding said latch bar in e'ngagemen't with said latch elements;-and" manually operable means for releasing-said latch'b'ar;

4; sectionalboom;comprising: apair'of boom sectfons ha vfiig conffonting end-plates; cooperatingseparable hinge elements at the upper margins of said end'plates adapted? to suppers said ena"p1stest61- pivbta1 movement into'contigl-ous relation; a plurality"latcli 'elements hav iitg'h'oolg extremities protruding from one of said end plates; other of said end plates having slots to aceominodate said latch etementsya latch bar disposed behind said other end plate" andin transverse relation to latch elements; springvmeans normally holding said latch bar inengagement with said latch elements; andmanually" operable means for releasing. said latch bar.

in a? vertical: plane, whereby. said axes may; be

brought into coincidence and said boom-sections relatively pivoted intocoaxial: relation;

. (f) aligning pinand socketmeans in the confronting, ends of said boom sections operable to'guide saids boom sections into accurate coaxialrelation and secure said boom sectionsagainst relative lateral displacement;

(g) and latch'means cooperating:with at least some of said'aligning pin and socket means andiwith said a hinge hook and bar means-tosecure said boom sec? tions against relative'axial displacement. 6. (a) A sectional boom for cranes, comprising: (by afirst boomseotion;

('0)- ahinge bar: means defining a first axis disposed:

above and across one end of saidfirst boomzsection; a second boom section;

(e) a hinged hook means defining a second" axis d'i's--:

posed above'and across one end or" said second boom section and'havingia'downwardly and outwardly di rectedop'enside accessible to said hinge bar means, when said boom sections are'angularly related but aligned in a" vertical plane,iwhereby said axes may be brought into coincidence and said boom sections relatively pivoted into coaxial relation;

( f) and latch and keeper means disposed at the ends of said boom sections at the side portionsthereof op posite fr'om said hinge hook andhinge bari means and cooper-able therewithupon movement of said.

boom sections into coaxial relation to locksaid boom sections against axial separation.

References Cited in the file of this patent ED" STATES PATENTS 2l,649,2 10 Marchese Aug. 18, 1953 2,809,756 Bannister oer. I5, 1957" 2,975,910 Conrad Mar. 21,1961 

5. (A) A SECTIONAL BOOM FOR CRANES, COMPRISING: (B) A FIRST BOOM SECTION; (C) A HINGE BAR MEANS DEFINING A FIRST AXIS DISPOSED ABOVE AND ACROSS ONE END OF SAID FIRST BOOM SECTION; (D) A SECOND BOOM SECTION; (E) A HINGE HOOK MEANS DEFINING A SECOND AXIS DISPOSED ABOVE AND ACROSS ONE END OF SAID SECOND BOOM SECTION AND HAVING A DOWNWARDLY AND OUTWARDLY DIRECTED OPEN SIDE ACCESSIBLE TO SAID HINGE BAR MEANS, WHEN SAID BOOM SECTIONS ARE ANGULARLY RELATED BUT ALIGNED IN A VERTICAL PLANE, WHEREBY SAID AXES MAY BE BROUGHT INTO COINCIDENCE AND SAID BOOM SECTIONS RELATIVELY PIVOTED INTO COAXIAL RELATION; (F) ALIGNING PIN AND SOCKET MEANS IN THE CONFRONTING ENDS OF SAID BOOM SECTIONS OPERABLE TO GUIDE SAID BOOM SECTIONS INTO ACCURATE COAXIAL RELATION AND SECURE SAID BOOM SECTIONS AGAINST RELATIVE LATERAL DISPLACEMENT; (G) AND LATCH MEANS COOPERATING WITH AT LEAST SOME OF SAID ALIGNING PIN AND SOCKET MEANS AND WITH SAID HINGE HOOK AND BAR MEANS TO SECURE SAID BOOM SECTIONS AGAINST RELATIVE AXIAL DISPLACEMENT. 